期刊文献+
共找到6篇文章
< 1 >
每页显示 20 50 100
Comparison of Block Design Nonparametric Subset Selection Rules Based on Alternative Scoring Rules
1
作者 Gary C. McDonald Sajidah Alsaeed 《Applied Mathematics》 2024年第5期355-389,共35页
This article compares the size of selected subsets using nonparametric subset selection rules with two different scoring rules for the observations. The scoring rules are based on the expected values of order statisti... This article compares the size of selected subsets using nonparametric subset selection rules with two different scoring rules for the observations. The scoring rules are based on the expected values of order statistics of the uniform distribution (yielding rank values) and of the normal distribution (yielding normal score values). The comparison is made using state motor vehicle traffic fatality rates, published in a 2016 article, with fifty-one states (including DC as a state) and over a nineteen-year period (1994 through 2012). The earlier study considered four block design selection rules—two for choosing a subset to contain the “best” population (i.e., state with lowest mean fatality rate) and two for the “worst” population (i.e., highest mean rate) with a probability of correct selection chosen to be 0.90. Two selection rules based on normal scores resulted in selected subset sizes substantially smaller than corresponding rules based on ranks (7 vs. 16 and 3 vs. 12). For two other selection rules, the subsets chosen were very close in size (within one). A comparison is also made using state homicide rates, published in a 2022 article, with fifty states and covering eight years. The results are qualitatively the same as those obtained with the motor vehicle traffic fatality rates. 展开更多
关键词 Order Statistics Rank Scoring Methods Probability of a Correct Selection Subset Size Motor vehicle traffic Fatality Rates Homicide Rates Asymptotic Distributions
下载PDF
Video-based measurement and data analysis of traffic flow on urban expressways 被引量:4
2
作者 Xian-Qing Zheng Zheng Wu Shi-Xiong Xu Ming-Min Guo Zhan-Xi Lin Ying-Ying Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第3期346-353,共8页
A new video-based measurement is proposed to collect and investigate traffic flow parameters. The output of the measurement is velocity-headway distance data pairs. Because density can be directly acquired by the reci... A new video-based measurement is proposed to collect and investigate traffic flow parameters. The output of the measurement is velocity-headway distance data pairs. Because density can be directly acquired by the reciprocal of headway distance, the data pairs have the advantage of better simultaneity than those from common detectors. By now, over 33 000 pairs of data have been collected from two road sections in the cities of Shanghai and Zhengzhou. Through analyzing the video files recording traffic movements on urban expressways, the following issues are studied:laws of vehicle velocity changing with headway distance, proportions of di0erent driving behaviors in the traffic system, and characteristics of traffic flow in snowy days. The results show that the real road traffic is very complex, and factors such as location and climate need to be taken into consideration in the formation of traffic flow models. 展开更多
关键词 traffic flow mode - Video-based - vehicle recog- nition. Driving behavior - Snowy day traffic
下载PDF
A Comparison of Machine Learning Techniques in the Carpooling Problem 被引量:1
3
作者 M. A. Arteaga Santos C. Méndez Santos +6 位作者 S. Ibarra Martínez J. A. Castán Rocha J. Laria Menchaca J. D. Terán Villanueva M. G. Treviño Berrones J. Pérez Cobos E. Castán Rocha 《Journal of Computer and Communications》 2020年第12期159-169,共11页
Urban traffic congestion is a severe and widely studied problem over the decade because of the negative impacts. However, in recent years some approaches emerge as proper and suitable solutions. The Carpooling initiat... Urban traffic congestion is a severe and widely studied problem over the decade because of the negative impacts. However, in recent years some approaches emerge as proper and suitable solutions. The Carpooling initiative is one of the most representative efforts to propitiate a responsible use of particular vehicles. Thus, the paper introduces a carpooling model considering the users’ preference to reach an appropriate match among drivers and passengers. In particular, the paper conducts a study of 6 of the most avid classified techniques in machine learning to create a model for the selection of travel companions. The experimental results show the models’ precision and assess the best cases using Friedman’s test. Finally, the conclusions emphasize the relevance of the proposed study and suggest that it is necessary to extend the proposal with more drives and passengers’ data. 展开更多
关键词 Carpooling Machine Learning Techniques vehicle traffic Congestion
下载PDF
An estimation of vehicle kilometer traveled and on-road emissions using the traffic volume and travel speed on road links in Incheon City 被引量:1
4
作者 Sungwoon Jung Jounghwa Kim +2 位作者 Jeongsoo Kim Dahee Hong Dongjoo Park 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第4期90-100,共11页
The objective of this study is to estimate the vehicle kilometer traveled(VKT) and on-road emissions using the traffic volume in urban. We estimated two VKT; one is based on registered vehicles and the other is base... The objective of this study is to estimate the vehicle kilometer traveled(VKT) and on-road emissions using the traffic volume in urban. We estimated two VKT; one is based on registered vehicles and the other is based on traffic volumes. VKT for registered vehicles was 2.11 times greater than that of the applied traffic volumes because each VKT estimation method is different. Therefore, we had to define the inner VKT is moved VKT inner in urban to compare two values. Also, we focused on freight modes because these are discharged much air pollutant emissions. From analysis results, we found middle and large trucks registered in other regions traveled to target city in order to carry freight, target city has included many industrial and logistics areas. Freight is transferred through the harbors,large logistics centers, or via locations before being moved to the final destination. During this process, most freight is moved by middle and large trucks, and trailers rather than small trucks for freight import and export. Therefore, these trucks from other areas are inflow more than registered vehicles. Most emissions from diesel trucks had been overestimated in comparison to VKT from applied traffic volumes in target city. From these findings, VKT is essential based on traffic volume and travel speed on road links in order to estimate accurately the emissions of diesel trucks in target city. Our findings support the estimation of the effect of on-road emissions on urban air quality in Korea. 展开更多
关键词 vehicle kilometer traveled On-road emissions traffic volume Travel speed Diesel trucks
原文传递
Influence of traffic on the temperature field of tunnel in cold region:A case study on the world’s longest highway spiral tunnel 被引量:2
5
作者 Yifan Jiang Jianyou Yu +6 位作者 Ping Zhou Feicong Zhou Jiayong Lin Jinyi Li Ming Lin Feiya Lei Zhijie Wang 《Underground Space》 SCIE EI CSCD 2023年第1期196-209,共14页
The impact of the piston wind caused by vehicle traffic on the temperature field distribution of the tunnel cannot be ignored,especially in spiral tunnels,where the temperature field distribution is more complicated t... The impact of the piston wind caused by vehicle traffic on the temperature field distribution of the tunnel cannot be ignored,especially in spiral tunnels,where the temperature field distribution is more complicated than that in straight tunnels.Based on the world’s longest highway spiral tunnel,this study explores the influence of traffic on the temperature fields of spiral and straight tunnels,and proposes a new design method for laying length of insulation layer.The results show that traffic has a significant effect on the temperature field dis-tribution in the tunnel.The influence degree of different traffic elements decreases in the following order:average vehicle speed>daily traffic>morning rush hour>evening rush hour.The temperature field distribution of spiral tunnels is asymmetry on the left and right compared with straight tunnels,while the influence degree of traffic on the outside of spiral tunnels is similar to that of straight tunnels.Due to the difference of wind direction and traffic direction at different tunnel openings,an asymmetric insulation layer laying method is proposed.It is suggested that the lengths of the insulation layers of the Jinjiazhuang Tunnel should be 1200 m for the right tunnel inlet,700 m for the right tunnel outlet,700 m for the left tunnel inlet,and 1400 m for the left tunnel outlet. 展开更多
关键词 Highway spiral tunnel vehicle traffic Cold Region Temperature field Length of insulation layer
原文传递
Range-rate tradeoffs in the communication between LED traffic lights and vehicles
6
作者 权进国 刘维浩 +1 位作者 金爽 张岩 《Chinese Optics Letters》 SCIE EI CAS CSCD 2013年第10期71-74,共4页
Visible light communication between light emitting diode(LED) traffic lights and vehicles with a receiving photodiode front-end is developed for intelligent transportation systems. In this letter, the communication da... Visible light communication between light emitting diode(LED) traffic lights and vehicles with a receiving photodiode front-end is developed for intelligent transportation systems. In this letter, the communication data rates for different ranges are evaluated. The data rates are based on real scenarios of the background noise and path losses and are experimentally obtained with a testing system built upon commercial offthe-shelf components. Comparisons of range-rate performance for different average noise levels are also conducted with the use of red/yellow/green LED lights. Results show that achieving the data rates of kilobits per second at a communication range of hundred meters is possible under the ordinary noise scenario, a finding that is highly significant for practical applications. 展开更多
关键词 LED RATE Range-rate tradeoffs in the communication between LED traffic lights and vehicles
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部